Photos: Gaza tunnels fulfill economic and military roles

A Palestinian man walks from the Egyptian side of the border on November 29, 2012, in a tunnel just repaired after it was bombed by Israel. Many of Rafah's tunnels have been opened and closed repeatedly, through war and other means. Patrick Baz / AFP / Getty Images

An Israeli army officer gives journalists a tour of a tunnel said to be used by Palestinians for cross-border attacks, July 25, 2014. Jack Guez / Reuters

A Hamas policeman stands on sand bags along the border with Egypt on September 1, 2013, in Rafah in the southern Gaza Strip, as smoke rises from the Egyptian side of the border following an explosion at a smuggling tunnel dug beneath the Gaza-Egypt border. Cairo's security forces have stepped up a crackdown on tunnels to the Gaza Strip since last year. Said Khatib / AFP / Getty Images

Palestinian workers unload cement pulled from a smuggling tunnel linking the Gaza Strip to Egypt, in Rafah, on November 29, 2012. Israeli air force jets bombed many of the tunnels in the southern Gaza Strip during its war against the Islamist movement Hamas, which rules the coastal Palestinian territory, for the eight-day Operation Pillar of Defense in November 2012. Patrick Baz / AFP / Getty Images

A tunnel worker carries food from Kentucky Fried Chicken to be delivered through an underground tunnel linking the Gaza Strip to Egypt, on May 13, 2013, in Rafah. When there's relative calm, fast food is just one of many goods transported by traders seeking to turn a buck by bringing in hard-to-get products to the Gaza Strip, which has been under an Israeli blockade since 2007. It's not exactly "fast" - taking several hours to arrive, with the Palestinian delivery company charging steep fees. AFP / Getty Images

A picture shows tents covering the entrances of tunnels along the Gaza-Egypt border, near Rafah, on February 15, 2014. Hundreds of tunnels were destroyed, especially following the Egyptian military's July 2013 overthrow of Islamist president Mohamed Morsi. Said Khatib / AFP / Getty Images

Smoke rises as the Egyptian army destroys a Gaza tunnel beneath the border between Egypt and the Gaza Strip, destroyed to prevent the import of rockets, among other items. During the summer 2014 conflict between Israel and Hamas, the Israeli air force has destroyed many similar tunnels to cut off Hamas' rocket supply. Eyad Al Baba / Anadolu Agency / Getty Images

A view of a tunnel reportedly dug by Palestinians beneath the border between the Gaza Strip and Israel, and uncovered by Israeli troops, on October 13, 2013. Prime Minister Benjamin Netanyahu congratulated the army "for exposing the Gaza terror tunnel" at a weekly cabinet meeting. David Buimovitch / AFP

Members of the Al Qassam Brigades, Hamas' military wing, in a tunnel that a group spokesman said could be used for offensive or defensive capabilities. Israel and Hamas have clashed several times on Israeli territory during the July 2014 conflict, as fighters emerged from tunnels on the eastern side of the border fence. Al Jazeera

In this handout photo provided by the Israeli government, Israeli Defense Minister Moshe Ya'alon tours the recently discovered tunnel linking Gaza to Israel while visiting the Southern Command and the Gaza Division on October 29, 2013, along the Israeli border with the Gaza Strip. Alon Besson / Ministry of Defense via Getty Images

Tunnels from Gaza to Israel, discovered and destroyed by Israeli soldiers. After the start of Operation Protective Edge, July 8, the Israeli Defense Force entered Gaza on the night of July 17 with the intended purpose of blowing up tunnels used by Palestinian armed groups that infiltrate Israel, and to destroy rocket-launching batteries used to launch missiles at Israel. Polaris

As of July 22, 2014, Israel said in Operation Protective Edge it had uncovered 66 entrances to some two dozen tunnels. Engineering Corps demolition teams used controlled explosions to destroy tunnels that often contained communications lines and barrel bombs. Israel said it had fully destroyed six of the passages that crossed the 25-mile frontier. David Buimovitch / AFP / Getty Images